Niklas Roy‘s studio workspace has a picturesque view of the street through its large storefront window–and vice versa. But what’s good for curious pedestrians isn’t good for Roy, so he installed a robotic curtain that automagically places itself right in the sightline of anyone trying to peer in. He calls it “My Little Piece of Privacy”: emphasis on “little.”

Roy hooked up his “small but smart” curtain to a hacked surveillance camera controlled by a laptop. (His computer code and plans are available for download here.) With the camera feeding visual information to the laptop, the curtain can “see” the position of potential peeping toms and jerk the curtain into place right in front of their faces. And that’s the genius: Notice in the video above how annoyed the curtain seems.

Of course, Roy’s petulant design actually does very little to protect his privacy — after all, that’s a pretty tiny curtain. But that’s the whole point. By whipping the ridiculously small obstruction backwards and forwards to track the movements of a determined voyeur, “My Little Piece of Privacy” calls embarrassing attention to the act of voyeurism itself. But the installation has an unintentionally useful effect even on those folks who don’t care about being shamed by a robot: the moving curtain is usually more interesting to onlookers than whatever he happens to be doing behind the window anyway.